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359ab9f5 MH |
1 | /* |
2 | * Fuel gauge driver for Maxim 17042 / 8966 / 8997 | |
3 | * Note that Maxim 8966 and 8997 are mfd and this is its subdevice. | |
4 | * | |
5 | * Copyright (C) 2011 Samsung Electronics | |
6 | * MyungJoo Ham <myungjoo.ham@samsung.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation; either version 2 of the License, or | |
11 | * (at your option) any later version. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License | |
19 | * along with this program; if not, write to the Free Software | |
20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
21 | * | |
22 | * This driver is based on max17040_battery.c | |
23 | */ | |
24 | ||
25 | #include <linux/init.h> | |
26 | #include <linux/slab.h> | |
27 | #include <linux/i2c.h> | |
28 | #include <linux/mod_devicetable.h> | |
29 | #include <linux/power_supply.h> | |
30 | #include <linux/power/max17042_battery.h> | |
31 | ||
359ab9f5 MH |
32 | struct max17042_chip { |
33 | struct i2c_client *client; | |
34 | struct power_supply battery; | |
35 | struct max17042_platform_data *pdata; | |
36 | }; | |
37 | ||
38 | static int max17042_write_reg(struct i2c_client *client, u8 reg, u16 value) | |
39 | { | |
40 | int ret = i2c_smbus_write_word_data(client, reg, value); | |
41 | ||
42 | if (ret < 0) | |
43 | dev_err(&client->dev, "%s: err %d\n", __func__, ret); | |
44 | ||
45 | return ret; | |
46 | } | |
47 | ||
48 | static int max17042_read_reg(struct i2c_client *client, u8 reg) | |
49 | { | |
50 | int ret = i2c_smbus_read_word_data(client, reg); | |
51 | ||
52 | if (ret < 0) | |
53 | dev_err(&client->dev, "%s: err %d\n", __func__, ret); | |
54 | ||
55 | return ret; | |
56 | } | |
57 | ||
086ef502 DK |
58 | static void max17042_set_reg(struct i2c_client *client, |
59 | struct max17042_reg_data *data, int size) | |
60 | { | |
61 | int i; | |
62 | ||
63 | for (i = 0; i < size; i++) | |
64 | max17042_write_reg(client, data[i].addr, data[i].data); | |
65 | } | |
66 | ||
359ab9f5 | 67 | static enum power_supply_property max17042_battery_props[] = { |
086ef502 DK |
68 | POWER_SUPPLY_PROP_PRESENT, |
69 | POWER_SUPPLY_PROP_CYCLE_COUNT, | |
70 | POWER_SUPPLY_PROP_VOLTAGE_MAX, | |
71 | POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN, | |
359ab9f5 MH |
72 | POWER_SUPPLY_PROP_VOLTAGE_NOW, |
73 | POWER_SUPPLY_PROP_VOLTAGE_AVG, | |
74 | POWER_SUPPLY_PROP_CAPACITY, | |
086ef502 DK |
75 | POWER_SUPPLY_PROP_CHARGE_FULL, |
76 | POWER_SUPPLY_PROP_TEMP, | |
77 | POWER_SUPPLY_PROP_CURRENT_NOW, | |
78 | POWER_SUPPLY_PROP_CURRENT_AVG, | |
359ab9f5 MH |
79 | }; |
80 | ||
81 | static int max17042_get_property(struct power_supply *psy, | |
82 | enum power_supply_property psp, | |
83 | union power_supply_propval *val) | |
84 | { | |
85 | struct max17042_chip *chip = container_of(psy, | |
86 | struct max17042_chip, battery); | |
87 | ||
88 | switch (psp) { | |
086ef502 DK |
89 | case POWER_SUPPLY_PROP_PRESENT: |
90 | val->intval = max17042_read_reg(chip->client, | |
91 | MAX17042_STATUS); | |
92 | if (val->intval & MAX17042_STATUS_BattAbsent) | |
93 | val->intval = 0; | |
94 | else | |
95 | val->intval = 1; | |
96 | break; | |
97 | case POWER_SUPPLY_PROP_CYCLE_COUNT: | |
98 | val->intval = max17042_read_reg(chip->client, | |
99 | MAX17042_Cycles); | |
100 | break; | |
101 | case POWER_SUPPLY_PROP_VOLTAGE_MAX: | |
102 | val->intval = max17042_read_reg(chip->client, | |
103 | MAX17042_MinMaxVolt); | |
104 | val->intval >>= 8; | |
105 | val->intval *= 20000; /* Units of LSB = 20mV */ | |
106 | break; | |
107 | case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN: | |
108 | val->intval = max17042_read_reg(chip->client, | |
109 | MAX17042_V_empty); | |
110 | val->intval >>= 7; | |
111 | val->intval *= 10000; /* Units of LSB = 10mV */ | |
112 | break; | |
359ab9f5 MH |
113 | case POWER_SUPPLY_PROP_VOLTAGE_NOW: |
114 | val->intval = max17042_read_reg(chip->client, | |
115 | MAX17042_VCELL) * 83; /* 1000 / 12 = 83 */ | |
116 | break; | |
117 | case POWER_SUPPLY_PROP_VOLTAGE_AVG: | |
118 | val->intval = max17042_read_reg(chip->client, | |
119 | MAX17042_AvgVCELL) * 83; | |
120 | break; | |
121 | case POWER_SUPPLY_PROP_CAPACITY: | |
122 | val->intval = max17042_read_reg(chip->client, | |
123 | MAX17042_SOC) / 256; | |
124 | break; | |
086ef502 DK |
125 | case POWER_SUPPLY_PROP_CHARGE_FULL: |
126 | val->intval = max17042_read_reg(chip->client, | |
127 | MAX17042_RepSOC); | |
128 | if ((val->intval / 256) >= MAX17042_BATTERY_FULL) | |
129 | val->intval = 1; | |
130 | else if (val->intval >= 0) | |
131 | val->intval = 0; | |
132 | break; | |
133 | case POWER_SUPPLY_PROP_TEMP: | |
134 | val->intval = max17042_read_reg(chip->client, | |
135 | MAX17042_TEMP); | |
136 | /* The value is signed. */ | |
137 | if (val->intval & 0x8000) { | |
138 | val->intval = (0x7fff & ~val->intval) + 1; | |
139 | val->intval *= -1; | |
140 | } | |
141 | /* The value is converted into deci-centigrade scale */ | |
142 | /* Units of LSB = 1 / 256 degree Celsius */ | |
143 | val->intval = val->intval * 10 / 256; | |
144 | break; | |
145 | case POWER_SUPPLY_PROP_CURRENT_NOW: | |
146 | if (chip->pdata->enable_current_sense) { | |
147 | val->intval = max17042_read_reg(chip->client, | |
148 | MAX17042_Current); | |
149 | if (val->intval & 0x8000) { | |
150 | /* Negative */ | |
151 | val->intval = ~val->intval & 0x7fff; | |
152 | val->intval++; | |
153 | val->intval *= -1; | |
154 | } | |
155 | val->intval >>= 4; | |
156 | val->intval *= 1000000 * 25 / chip->pdata->r_sns; | |
157 | } else { | |
158 | return -EINVAL; | |
159 | } | |
160 | break; | |
161 | case POWER_SUPPLY_PROP_CURRENT_AVG: | |
162 | if (chip->pdata->enable_current_sense) { | |
163 | val->intval = max17042_read_reg(chip->client, | |
164 | MAX17042_AvgCurrent); | |
165 | if (val->intval & 0x8000) { | |
166 | /* Negative */ | |
167 | val->intval = ~val->intval & 0x7fff; | |
168 | val->intval++; | |
169 | val->intval *= -1; | |
170 | } | |
171 | val->intval *= 1562500 / chip->pdata->r_sns; | |
172 | } else { | |
173 | return -EINVAL; | |
174 | } | |
175 | break; | |
359ab9f5 MH |
176 | default: |
177 | return -EINVAL; | |
178 | } | |
179 | return 0; | |
180 | } | |
181 | ||
182 | static int __devinit max17042_probe(struct i2c_client *client, | |
183 | const struct i2c_device_id *id) | |
184 | { | |
185 | struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); | |
186 | struct max17042_chip *chip; | |
187 | int ret; | |
188 | ||
189 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) | |
190 | return -EIO; | |
191 | ||
192 | chip = kzalloc(sizeof(*chip), GFP_KERNEL); | |
193 | if (!chip) | |
194 | return -ENOMEM; | |
195 | ||
196 | chip->client = client; | |
197 | chip->pdata = client->dev.platform_data; | |
198 | ||
199 | i2c_set_clientdata(client, chip); | |
200 | ||
201 | chip->battery.name = "max17042_battery"; | |
202 | chip->battery.type = POWER_SUPPLY_TYPE_BATTERY; | |
203 | chip->battery.get_property = max17042_get_property; | |
204 | chip->battery.properties = max17042_battery_props; | |
205 | chip->battery.num_properties = ARRAY_SIZE(max17042_battery_props); | |
206 | ||
086ef502 DK |
207 | /* When current is not measured, |
208 | * CURRENT_NOW and CURRENT_AVG properties should be invisible. */ | |
209 | if (!chip->pdata->enable_current_sense) | |
210 | chip->battery.num_properties -= 2; | |
211 | ||
359ab9f5 MH |
212 | ret = power_supply_register(&client->dev, &chip->battery); |
213 | if (ret) { | |
214 | dev_err(&client->dev, "failed: power supply register\n"); | |
359ab9f5 MH |
215 | kfree(chip); |
216 | return ret; | |
217 | } | |
218 | ||
086ef502 DK |
219 | /* Initialize registers according to values from the platform data */ |
220 | if (chip->pdata->init_data) | |
221 | max17042_set_reg(client, chip->pdata->init_data, | |
222 | chip->pdata->num_init_data); | |
223 | ||
359ab9f5 MH |
224 | if (!chip->pdata->enable_current_sense) { |
225 | max17042_write_reg(client, MAX17042_CGAIN, 0x0000); | |
226 | max17042_write_reg(client, MAX17042_MiscCFG, 0x0003); | |
227 | max17042_write_reg(client, MAX17042_LearnCFG, 0x0007); | |
086ef502 DK |
228 | } else { |
229 | if (chip->pdata->r_sns == 0) | |
230 | chip->pdata->r_sns = MAX17042_DEFAULT_SNS_RESISTOR; | |
359ab9f5 MH |
231 | } |
232 | ||
233 | return 0; | |
234 | } | |
235 | ||
236 | static int __devexit max17042_remove(struct i2c_client *client) | |
237 | { | |
238 | struct max17042_chip *chip = i2c_get_clientdata(client); | |
239 | ||
240 | power_supply_unregister(&chip->battery); | |
359ab9f5 MH |
241 | kfree(chip); |
242 | return 0; | |
243 | } | |
244 | ||
245 | static const struct i2c_device_id max17042_id[] = { | |
246 | { "max17042", 0 }, | |
247 | { } | |
248 | }; | |
249 | MODULE_DEVICE_TABLE(i2c, max17042_id); | |
250 | ||
251 | static struct i2c_driver max17042_i2c_driver = { | |
252 | .driver = { | |
253 | .name = "max17042", | |
254 | }, | |
255 | .probe = max17042_probe, | |
256 | .remove = __devexit_p(max17042_remove), | |
257 | .id_table = max17042_id, | |
258 | }; | |
259 | ||
260 | static int __init max17042_init(void) | |
261 | { | |
262 | return i2c_add_driver(&max17042_i2c_driver); | |
263 | } | |
264 | module_init(max17042_init); | |
265 | ||
266 | static void __exit max17042_exit(void) | |
267 | { | |
268 | i2c_del_driver(&max17042_i2c_driver); | |
269 | } | |
270 | module_exit(max17042_exit); | |
271 | ||
272 | MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); | |
273 | MODULE_DESCRIPTION("MAX17042 Fuel Gauge"); | |
274 | MODULE_LICENSE("GPL"); |